Field of the Invention
The present invention relates to a near-infrared cut filter having a new structure and a solid-state image pickup device including the same.
Background Art
A camera converts light into an electric signal using a CMOS sensor to form an image. In order to implement a high quality image in accordance with a high pixel of a camera, it is a trend to apply a newly developed back side illuminated type (BSI type) CMOS sensor to a main camera, instead of a front side illuminated type (FSI type) CMOS sensor which has been frequently used in the related art. In the FSI type CMOS sensor, a wiring line is formed above a photodiode (PD) so that light is partially blocked. In contrast, in the BSI type CMOS sensor, the wiring line is formed below the photodiode in order to receive more light, so that an image is 70% or brighter than an image formed by the FSI type CMOS sensor. Therefore, the BSI type is adopted in the most of 8 million or higher pixel cameras.
The BSI type CMOS sensor has the above-mentioned advantage because more incident light reaches the photodiode as compared with the FSI type CMOS sensor. More incident light reaches the photodiode because the BSI type CMOS sensor receives light having a relatively large incident angle due to structural improvement.
The incident angle of incident light is increased while improving a structure of the photodiode of the camera in order to receive more incident light. However, the broader incident angle of the incident light may cause a difference in a color sense.